Almost 100,000 species have been assessed so far for this inventory of endangered species. Of these, more than a quarter are threatened with extinction, ranging from Madagascar's lemurs to amphibians like frogs and salamanders, and plants such as conifers and orchids.
4. Habitat conversion drives biodiversity loss
According to IPBES, only a quarter of land on Earth is substantively free of the impacts of human activities. This is projected to decline to just one-tenth by 2050.
"The issue of land use is central to the major environmental challenges we are experiencing," Prof Mercedes Bustamante of the University of Brasilia told BBC News.
Since 2001, Indonesia has lost millions of hectares of pristine rainforest. Losses in 2018 declined by around 40% thanks to stricter government legislation and a wet period that limited forest fires, but nonetheless palm oil plantations have gradually eroded the only remaining habitats of endangered orang-utan populations.
In the lowland forests of South East Asia, on islands like Borneo and Sumatra, IPBES predicts that one in three types of birds and nearly a quarter of all mammals will be lost if the rate of forest degradation continues.
5. Some of the last great rainforests are being wiped out
The Amazon region holds the largest tropical rainforest in the world, which is home to plant and animal species that are still being discovered.
Rondônia, in the western part of the Amazon, is one of the most deforested parts of the Amazon region. Trees are being lost as forests are cut down for growing crops or for pastures to graze cattle, as well as for logging and mining.
Over time, the landscape becomes a mixture of cleared fields, settlements and fragments of forest.
IPBES will formally release its first intergovernmental assessment on Monday 6 May, detailing the past losses and future prospects for nature and humans.